I think Linux generally is a great thing,worth experience and wonder.Unfortunately,being a complete novice and not exactly a teenager,the smallest obstacle on the path to enlightenment,grows to a size of a mountain.After disastrous attempt to update my Linux Mint,my machine was no longer responsive and I moved the hard disk to a "new" desktop,which runs also Linux Mint.Any approach to open up the disk from my "old" machine was a failure.The hdd icon has a big X over it and after clicking open from right hand button menu,a message/field requiring authentication pops up.My humble question is-authenticate with what? Certainly not with my old password,which is no good any more or my new password on the new machine.The problem is probably not a problem and looks silly,alas,not for me